20728981

素因数分解:

$7^1\times {\mathrm{13}}^1\times {\mathrm{19}}^2\times {\mathrm{631}}^1$

素因数の和:689

約数の個数: 24

約数和(自身を含む): 26968704

約数和(自身を除く): 6239723

約数列:

[1, 7, 13, 19, 91, 133, 247, 361, 631, 1729, 2527, 4417, 4693, 8203, 11989, 32851, 57421, 83923, 155857, 227791, 1090999, 1594537, 2961283, 20728981]

約数ペア:

[(1, 20728981), (7, 2961283), (13, 1594537), (19, 1090999), (91, 227791), (133, 155857), (247, 83923), (361, 57421), (631, 32851), (1729, 11989), (2527, 8203), (4417, 4693)]